Knife blade



FIG. 1 is a top, view of a knife blade, showing my new design;

FIG. 2 is a left side view thereof;

FIG. 3 is a front view thereof;

FIG. 4 is a right view thereof;

FIG. 5 is a bottom view thereof; and,

FIG. 6 is a perspective viewed thereof. 

CLAIM The ornamental design for a knife blade, as shown, and described. 